1. Field of the Invention
This invention relates to the application of zippers to lengths of material. The invention will be described with reference to the application of a zipper to material intended for forming the end panel in a mattress construction. Such constructions utilize a mattress cover having one end panel with a zipper opening whereby the insertion of the mattress filler is facilitated. It will be understood, however, that other uses for the system of the invention are contemplated.
The invention finds particular utility in the application of zippers to materials which define a pattern. An important aspect of the invention involves the application of a zipper to a length of material in a fashion such that the separate pieces of material, when rejoined by the zipper, will automatically achieve matching of the pattern portions in the respective pieces.
2. Description of the Prior Art
Standard zipper constructions comprise separate tape sections with each section having one edge supporting the zipper teeth. The tape sections also include portions extending away from these edges whereby a sewing machine or the like can be utilized for attaching the tape sections to a fabric or other material. In a typical operation, two separate pieces of material are each provided with a tape section, and the pieces can then be joined by utilizing a zipper closer.
Problems arise where the material defines a pattern since for most suitable appearance, the pattern portion of one piece should match the pattern portion of a separate piece when the pieces are joined. Ordinary practice involves cutting the material and applying the zipper tape sections in a fashion such that the patterns can be matched. Particularly in the case of a mass production operation, exact matching can be time-consuming. Accordingly, where high production rates are desired, the matching is often sacrificed.